Clever trick! It would be even better if it worked with Parasolid, but you don't get the option to not knit the surfaces. It does work with STEP, which I would pick in preference to IGES, being less likely to come up with errors on the round trip.

The reason I was posing the question was I had a client model which was an export to a step file as a single surface which had nearly 15k faces.

Because of the size and difficulty in opening the file I was task with cutting it down to something useable. However most features would crash solidworks including insert into assembly or insert part into a part. So the only way was to modify file somehow.

What was happening though (after juicing up the computer with asecond GPU) was when I was copying the faces I wanted, deleting the full surface model (or surpressing) saving then closing and opening the file I found that the faces renumbered themselves which meant the faces I copied were no longer the faces I copied, but they were in fact just randomised.

This is why I thought a 'surface explode' tool coined by Alin above would be a good idea.

I eventually found that by saving the model as a parasolid it drastically reduced the file size when it got reparsed and it also solved the funky musical chair effect on the faces.

Alin... I will need to try the IGES trick you spoke of. I often find converting formats can get around sticky spots, especially if the feature tree is of no consequence.